1. Field of the Invention
This invention pertains generally to power-line carrier communication and, more particularly, to couplers for providing power-line carrier communication between two or more power-lines. The invention also relates to a panelboard employing a coupler for providing power-line carrier communication between two or more power-lines.
2. Background Information
An electrical distribution system within an industrial, commercial or residential property starts at the utility service entrance and ends at the final utilization equipment or loads. The service entrance includes the utility company""s wattmeter or kWh meter. Beyond the utility company""s meter is a main circuit interrupting device, such as a circuit breaker. The main circuit breaker supplies power to a number of feeder circuits which, in turn, power a number of branch circuits. In a small system, such as a home, the main circuits directly feed individual branch circuits and no feeder circuits are employed. The electrical utilization loads are normally located on the branch circuits.
It is known to employ serial communication on power-lines based upon standard open protocols, such as asynchronous power-line carrier CEBus and X10. See, for example, U.S. Pat. Nos. 5,949,779 (CEBus); and 5,491,463 (X-10).
A CEBus master, for example, may be interconnected with and powered through one or both lines of a conventional two-line residential power system, or one, two or three lines of a three-phase industrial power system. The CEBus master may employ a communication medium, such as a wide area network, between a CEBus power-line carrier local area network and, for example, a utility company at a remote location. The communication medium may be any of various systems such as, for example, telephone, fiber optic, cable television or radio frequency (RF). The CEBus power-line carrier local area network provides communication between the CEBus master and one or more CEBus slaves on that network.
It is known to employ a CEBus passive coupler to transfer CEBus command signals generated on one phase of a plural-phase power system to another of those phases. In this manner, all CEBus products on one of the phases may communicate with other CEBus products on the other phase(s). Discrete wires are employed to connect the CEBus passive coupler between the phases of power and to the neutral power-line. Alternatively, rather than directly connecting the wires to the phase conductors, the wires may be connected to the load side of the phase circuit breakers.
Although CEBus passive couplers expand the scope of CEBus communication, there is room for improvement.
The present invention provides improvements in the mechanical packaging of couplers for power-line carrier signals.
In accordance with one aspect of the invention, a coupler for a pair of power-lines comprises: a housing having a form of a circuit breaker; means for electrically connecting to a neutral power-line; a first circuit breaker stab disposed on the housing; a second circuit breaker stab disposed on the housing; and means for coupling a power-line carrier signal as referenced to the neutral power-line between one of the first and second circuit breaker stabs, and the other of the first and second circuit breaker stabs.
As another aspect of the invention, a coupler for three power-lines comprises: a housing having a form of a circuit breaker; means for electrically connecting to a neutral power-line; a first circuit breaker stab disposed on the housing; a second circuit breaker stab disposed on the housing; a third circuit breaker stab disposed on the housing; means for coupling a power-line carrier signal as referenced to the neutral power-line between the first circuit breaker stab and the second circuit breaker stab; and means for coupling the power-line carrier signal between one of the first and second circuit breaker stabs, and the third circuit breaker stab.
As a still further aspect of the invention, a panelboard apparatus is for use with a plurality of electrical switching apparatus which switch a plurality of circuits from a plurality of power-lines through a plurality of loads. The panelboard apparatus comprises an enclosure; at least one electrical switching apparatus, with the enclosure for holding up to the plurality of electrical switching apparatus including the at least one electrical switching apparatus; and a coupler for at least a pair of the power-lines. The coupler comprises a housing having a form of a circuit breaker; means for electrically connecting to a neutral power-line; a first circuit breaker stab disposed on the housing for engaging one of the pair of the power-lines; at least a second circuit breaker stab disposed on the housing for engaging another of the pair of the power-lines; and means for coupling a power-line carrier signal as referenced to the neutral power-line between one of the first and second circuit breaker stabs for a first power-line of the pair of the power-lines, and the other of the first and second circuit breaker stabs for a second power-line of the pair of the power-lines.